X-Git-Url: http://git.samba.org/samba.git/?p=sfrench%2Fcifs-2.6.git;a=blobdiff_plain;f=fs%2Fbuffer.c;h=912d70169fca0f0b3621b055b5986e0b58fd682f;hp=9c8eb9b6db6aace3ef93edc5c8369ba48ecfb4f4;hb=e64855c6cfaa;hpb=4a1ff03faf0562665c5b0d7130658bf13d65426e diff --git a/fs/buffer.c b/fs/buffer.c index 9c8eb9b6db6a..912d70169fca 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -43,6 +43,7 @@ #include #include #include +#include #include static int fsync_buffers_list(spinlock_t *lock, struct list_head *list); @@ -351,7 +352,7 @@ void end_buffer_async_write(struct buffer_head *bh, int uptodate) set_buffer_uptodate(bh); } else { buffer_io_error(bh, ", lost async page write"); - set_bit(AS_EIO, &page->mapping->flags); + mapping_set_error(page->mapping, -EIO); set_buffer_write_io_error(bh); clear_buffer_uptodate(bh); SetPageError(page); @@ -753,7 +754,7 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list) * still in flight on potentially older * contents. */ - write_dirty_buffer(bh, WRITE_SYNC); + write_dirty_buffer(bh, REQ_SYNC); /* * Kick off IO for the previous mapping. Note @@ -1078,7 +1079,7 @@ grow_buffers(struct block_device *bdev, sector_t block, int size, gfp_t gfp) return grow_dev_page(bdev, block, index, size, sizebits, gfp); } -struct buffer_head * +static struct buffer_head * __getblk_slow(struct block_device *bdev, sector_t block, unsigned size, gfp_t gfp) { @@ -1109,7 +1110,6 @@ __getblk_slow(struct block_device *bdev, sector_t block, free_more_memory(); } } -EXPORT_SYMBOL(__getblk_slow); /* * The relationship between dirty buffers and dirty pages: @@ -1637,6 +1637,81 @@ void unmap_underlying_metadata(struct block_device *bdev, sector_t block) } EXPORT_SYMBOL(unmap_underlying_metadata); +/** + * clean_bdev_aliases: clean a range of buffers in block device + * @bdev: Block device to clean buffers in + * @block: Start of a range of blocks to clean + * @len: Number of blocks to clean + * + * We are taking a range of blocks for data and we don't want writeback of any + * buffer-cache aliases starting from return from this function and until the + * moment when something will explicitly mark the buffer dirty (hopefully that + * will not happen until we will free that block ;-) We don't even need to mark + * it not-uptodate - nobody can expect anything from a newly allocated buffer + * anyway. We used to use unmap_buffer() for such invalidation, but that was + * wrong. We definitely don't want to mark the alias unmapped, for example - it + * would confuse anyone who might pick it with bread() afterwards... + * + * Also.. Note that bforget() doesn't lock the buffer. So there can be + * writeout I/O going on against recently-freed buffers. We don't wait on that + * I/O in bforget() - it's more efficient to wait on the I/O only if we really + * need to. That happens here. + */ +void clean_bdev_aliases(struct block_device *bdev, sector_t block, sector_t len) +{ + struct inode *bd_inode = bdev->bd_inode; + struct address_space *bd_mapping = bd_inode->i_mapping; + struct pagevec pvec; + pgoff_t index = block >> (PAGE_SHIFT - bd_inode->i_blkbits); + pgoff_t end; + int i; + struct buffer_head *bh; + struct buffer_head *head; + + end = (block + len - 1) >> (PAGE_SHIFT - bd_inode->i_blkbits); + pagevec_init(&pvec, 0); + while (index <= end && pagevec_lookup(&pvec, bd_mapping, index, + min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1)) { + for (i = 0; i < pagevec_count(&pvec); i++) { + struct page *page = pvec.pages[i]; + + index = page->index; + if (index > end) + break; + if (!page_has_buffers(page)) + continue; + /* + * We use page lock instead of bd_mapping->private_lock + * to pin buffers here since we can afford to sleep and + * it scales better than a global spinlock lock. + */ + lock_page(page); + /* Recheck when the page is locked which pins bhs */ + if (!page_has_buffers(page)) + goto unlock_page; + head = page_buffers(page); + bh = head; + do { + if (!buffer_mapped(bh)) + goto next; + if (bh->b_blocknr >= block + len) + break; + clear_buffer_dirty(bh); + wait_on_buffer(bh); + clear_buffer_req(bh); +next: + bh = bh->b_this_page; + } while (bh != head); +unlock_page: + unlock_page(page); + } + pagevec_release(&pvec); + cond_resched(); + index++; + } +} +EXPORT_SYMBOL(clean_bdev_aliases); + /* * Size is a power-of-two in the range 512..PAGE_SIZE, * and the case we care about most is PAGE_SIZE. @@ -1685,7 +1760,7 @@ static struct buffer_head *create_page_buffers(struct page *page, struct inode * * prevents this contention from occurring. * * If block_write_full_page() is called with wbc->sync_mode == - * WB_SYNC_ALL, the writes are posted using WRITE_SYNC; this + * WB_SYNC_ALL, the writes are posted using REQ_SYNC; this * causes the writes to be flagged as synchronous writes. */ int __block_write_full_page(struct inode *inode, struct page *page, @@ -1698,7 +1773,7 @@ int __block_write_full_page(struct inode *inode, struct page *page, struct buffer_head *bh, *head; unsigned int blocksize, bbits; int nr_underway = 0; - int write_flags = (wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : 0); + int write_flags = wbc_to_write_flags(wbc); head = create_page_buffers(page, inode, (1 << BH_Dirty)|(1 << BH_Uptodate)); @@ -1746,8 +1821,7 @@ int __block_write_full_page(struct inode *inode, struct page *page, if (buffer_new(bh)) { /* blockdev mappings never come here */ clear_buffer_new(bh); - unmap_underlying_metadata(bh->b_bdev, - bh->b_blocknr); + clean_bdev_bh_alias(bh); } } bh = bh->b_this_page; @@ -1993,8 +2067,7 @@ int __block_write_begin_int(struct page *page, loff_t pos, unsigned len, } if (buffer_new(bh)) { - unmap_underlying_metadata(bh->b_bdev, - bh->b_blocknr); + clean_bdev_bh_alias(bh); if (PageUptodate(page)) { clear_buffer_new(bh); set_buffer_uptodate(bh); @@ -2634,7 +2707,7 @@ int nobh_write_begin(struct address_space *mapping, if (!buffer_mapped(bh)) is_mapped_to_disk = 0; if (buffer_new(bh)) - unmap_underlying_metadata(bh->b_bdev, bh->b_blocknr); + clean_bdev_bh_alias(bh); if (PageUptodate(page)) { set_buffer_uptodate(bh); continue; @@ -3119,7 +3192,7 @@ EXPORT_SYMBOL(submit_bh); /** * ll_rw_block: low-level access to block devices (DEPRECATED) * @op: whether to %READ or %WRITE - * @op_flags: rq_flag_bits + * @op_flags: req_flag_bits * @nr: number of &struct buffer_heads in the array * @bhs: array of pointers to &struct buffer_head * @@ -3211,7 +3284,7 @@ EXPORT_SYMBOL(__sync_dirty_buffer); int sync_dirty_buffer(struct buffer_head *bh) { - return __sync_dirty_buffer(bh, WRITE_SYNC); + return __sync_dirty_buffer(bh, REQ_SYNC); } EXPORT_SYMBOL(sync_dirty_buffer); @@ -3250,7 +3323,7 @@ drop_buffers(struct page *page, struct buffer_head **buffers_to_free) bh = head; do { if (buffer_write_io_error(bh) && page->mapping) - set_bit(AS_EIO, &page->mapping->flags); + mapping_set_error(page->mapping, -EIO); if (buffer_busy(bh)) goto failed; bh = bh->b_this_page;